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71.
Effect of sensory denervation with capsaicin on liver fibrosis induced by common bile duct ligation in rat 总被引:2,自引:0,他引:2
Alessandro Casini Irmgard Th. Lippe Stefano Evangelista Pierangelo Geppetti Paolo Santicioli Carmelo Urso Milena Paglierani Carlo Alberto Maggi Calogero Surrenti 《Journal of hepatology》1990,11(3):302-312
Hepatic fibrosis represents an important stage in the progression of chronic liver disease to cirrhosis. In the present paper we have investigated whether capsaicin-sensitive neuropeptide-containing sensory neurons may participate in the development of liver fibrosis. The expression of hepatic fibrosis induced by common bile duct obstruction has been studied both in capsaicin- and vehicle-treated rats. Common bile duct-induced liver fibrosis was less marked in capsaicin-treated rats than in vehicle-treated rats. Diffuse alterations of liver parenchyma structure with marked collagen deposition and nodular regeneration occurred 8 weeks after common bile duct ligation in vehicle-treated animals, while none of the capsaicin-treated rats exhibited the formation of complete connective septa altering the parenchyma architecture. Both vehicle- and capsaicin-treated rats showed an increasing number of desmin-positive cells in the perivenular zone, but the density of these cells was lower in treated animals than in untreated rats. The hydroxyproline content of the liver increased after common bile duct ligation in a time-dependent manner. Eight weeks after bile duct obstruction vehicle-treated rats showed a 7-fold increase of liver collagen content in comparison to normal animals. This enhancement was about 3.5-fold in capsaicin-treated rats. These findings raise the possibility that the peripheral release of neuropeptides stored in sensory nerves might participate in the development of liver fibrosis following common bile duct obstruction. 相似文献
72.
Silvia Marino Andrea Di Cataldo Gaetano Magro Salvatore D'Amico Milena La Spina Vincenzo Di Benedetto Mariaclaudia Meli Carla Moscheo Giovanna Russo 《Clinical Case Reports》2015,3(3):179-182
We report a rare clinical presentation of childhood Hodgkin lymphoma with immune thrombocytopenia. Diagnostic biopsy of the abdominal mass was performed after administration of intravenous immunoglobulins, steroids, and platelet transfusion. Concomitant thrombocytopenia complicated the whole diagnosis work up and the initial management of neoplasia. 相似文献
73.
Anna-Marie Lauermannov Filip Anton
ík Michal Lojka Ondej Jankovský Milena Pavlíkov Adam Pivk Martina Zlesk Zbyek Pavlík 《Materials》2020,13(24)
A high-performance magnesium oxychloride cement (MOC) composite composed of silica sand, diatomite powder, and doped with graphene nanoplatelets was prepared and characterized. Diatomite was used as a 10 vol.% replacement for silica sand. The dosage of graphene was 0.5 wt.% of the sum of the MgO and MgCl2·6H2O masses. The broad product characterization included high-resolution transmission electron microscopy, X-ray diffraction, X-ray fluorescence, scanning electron microscopy and energy dispersive spectroscopy analyses. The macrostructural parameters, pore size distribution, mechanical resistance, stiffness, hygric and thermal parameters of the composites matured for 28-days were also the subject of investigation. The combination of diatomite and graphene nanoplatelets greatly reduced the porosity and average pore size in comparison with the reference material composed of MOC and silica sand. In the developed composites, well stable and mechanically resistant phase 5 was the only precipitated compound. Therefore, the developed composite shows high compactness, strength, and low water imbibition which ensure high application potential of this novel type of material in the construction industry. 相似文献
74.
Petr Heneberg Jiljí Sitko Jiří Bizos Lucie Kocková Milena Malá Ivan Literák 《Parasitology research》2014,113(9):3211-3220
Collyriclum faba (Plagiochiida: Collyriclidae) adults occur in pairs within subcutaneous cysts. Here, we tested the extensive C. faba infrapopulation for five DNA loci known to display variability among Central European C. faba individuals. The infrapopulation tested shared 100 % similarity in four of the five mitochondrial and nuclear DNA loci tested. Contrariwise, the internal transcribed spacer 1 (ITS1) loci in all but one individual differed from each other. We found only 0.0–1.5 base substitutions per 1,000 sites within the cysts, while we found 0.7–9.0 substitutions between the cysts of the single host and 3.0–9.0 substitutions when comparing C. faba individuals isolated from different host individuals. We observed the most of the ITS1 variability within 48 bp repetitive sequences featured by the chi-like sequence 5′-GCTTGTCTGCC-3′ at their beginning. Similarly to the extensive C. faba infrapopulation examined, we determined the presence of highly variable number of repetitive sequences within the ITS1 locus of C. faba isolated from multiple host species and from various geographic locations. While similar variability was observed earlier in mutually unrelated specimens of several Schistosomatidae and Microphallidae species, here, we for the first time document it among multiple individuals of a single infracommunity possessing single mitochondrial haplotype. Lower ITS1 evolutionary divergence rates observed between individuals within the cysts when compared to those between the cysts suggest that the recombination occurs at multiple stages of the life cycle. We propose DNA recombination involving chi-like sequences to serve as a general feature shared by multiple families of digenetic trematodes to increase genetic diversity of their polyembryonic populations infecting their definitive hosts. 相似文献
75.
76.
Recent studies indicate that not only the anthelminthic levamisole but also the racemate tetramisole (R‐/S‐phenyltetraimidazothiazole, PTHIT) was found as an adulterant for cocaine. We herein report on the investigation of the prevalence of PTHIT among cocaine‐positive hair samples and the discrimination of the presence of its stereoisomers levamisole and dexamisole. Cocaine‐positive hair samples were collected in a forensic context in 2015 and mainly 2017 (n = 724). Cocaine and PTHIT concentrations have been determined by achiral liquid chromatography–tandem mass spectrometry (LC–MS/MS). For distinction of levamisole/dexamisole chiral LC–MS/MS was performed. Cocaine hair concentrations ranged from 500 (cut‐off) to approximately 800 000 pg/mg. The study demonstrates a strong prevalence of PTHIT in cocaine users' hair (87%, n = 627). PTHIT hair concentrations ranged from below LLOQ 3.5 to approximately 61 000 pg/mg (median: 260 pg/mg). Surprisingly, enantiomeric ratios of levamisole/dexamisole ranged from 0.17 to 1.34 (median: 0.63). Therefore, PTHIT‐adulterated street cocaine samples (n = 24) seized between 2013 and 2016 were tested. Samples mainly contained racemic tetramisole (87.5%), only one sample contained levamisole only and two samples contained non‐racemic PTHIT. Our experiments suggest that the presence of tetramisole in biological samples may have hitherto been underestimated. Most probably higher dexamisole than levamisole concentrations in hair specimens arise from stereoselective metabolism and/or elimination. This is particularly important in light of the different pharmacological activities of the two enantiomers and potentially different adverse effects. Toxicological interpretations in intoxication cases with adulterated cocaine should not only consider levamisole but also tetramisole and terminology in scientific contributions should be used accordingly. 相似文献
77.
Paul Swoboda Hans-Peter Fuehrer Benedikt Ley Peter Starzengruber Kamala Ley-Thriemer Mariella Jung Julia Matt Markus A. Fally Milena K. S. Mueller Johannes A. B. Reismann Rashidul Haque Wasif A. Khan Harald Noedl 《The American journal of tropical medicine and hygiene》2014,90(2):377-382
In malaria-endemic regions any febrile case is likely to be classified as malaria based on presumptive diagnosis largely caused by a lack of diagnostic resources. A district-wide prevalence study assessing etiologies of fever in 659 patients recruited in rural and semi-urban areas of Bandarban district in southeastern Bangladesh revealed high proportions of seropositivity for selected infectious diseases (leptospirosis, typhoid fever) potentially being misdiagnosed as malaria because of similarities in the clinical presentation. In an area with point prevalences of more than 40% for malaria among fever cases, even higher seroprevalence rates of leptospirosis and typhoid fever provide evidence of a major persistent reservoir of these pathogens. 相似文献
78.
Sabrina Lindemberg Sergio Chermont M?nica Quint?o Milena Derossi Sergio Guilhon Sabrina Bernardez Luana Marchese Wolney Martins Ant?nio Claudio L. Nóbrega Evandro Tinoco Mesquita 《Arquivos brasileiros de cardiologia》2014,102(3):279-287
Background
Heart rate recovery at one minute of rest (HRR1) is a predictor of mortality in heart failure (HF), but its prognosis has not been assessed at six-minute walk test (6MWT) in these patients.Objective
This study aimed to determine the HRR1 at 6MWT in patients with HF and its correlation with six-minute walk distance (6MWD).Methods
Cross-sectional, controlled protocol with 161 individuals, 126 patients with stable systolic HF, allocated into 2 groups (G1 and G2) receiving or not β-blocker and 35 volunteers in control group (G3) had HRR1 recorded at the 6MWT.Results
HRR1 and 6MWD were significantly different in the 3 groups. Mean values of HRR1 and 6MWD were: HRR1 = 12 ± 14 beat/min G1; 18 ± 16 beat/min G2 and 21 ± 13 beat/min G3; 6MWD = 423 ± 102 m G1; 396 ± 101m G2 and 484 ± 96 m G3 (p < 0.05). Results showed a correlation between HRR1 and 6MWD in G1(r = 0.3; p = 0.04) and in G3(r = 0.4; p= 0.03), but not in G2 (r= 0.12; p= 0.48).Conclusion
HRR1 response was attenuated in patients using βB and showed correlation with 6MWD, reflecting better exercise tolerance. HRR1 after 6MWT seems to represent an alternative when treadmill tests could not be tolerated. 相似文献79.
Igor Bastos Polonio Milena Marques Pagliareli Acencio Rogério Pazetti Francine Maria de Almeida Bárbara Soares da Silva Karina Aparecida Bonifácio Pereira Rogério Souza 《Jornal brasileiro de pneumologia》2014,40(4):421-424
We assessed the effects of lodenafil on hemodynamics and inflammation in the rat
model of monocrotaline-induced pulmonary hypertension (PH). Thirty male
Sprague-Dawley rats were randomly divided into three groups: control; monocrotaline
(experimental model); and lodenafil (experimental model followed by lodenafil
treatment, p.o., 5 mg/kg daily for 28 days) Mean pulmonary artery pressure (mPAP) was
obtained by right heart catheterization. We investigated right ventricular
hypertrophy (RVH) and IL-1 levels in lung fragments. The number of cases of RVH was
significantly higher in the monocrotaline group than in the lodenafil and control
groups, as were mPAP and IL-1 levels. We conclude that lodenafil can prevent
monocrotaline-induced PH, RVH, and inflammation. 相似文献
80.